Commodore VIC-20 User Manual page 52

the screen and type [r] [Q] [n] .If you have any errors,
retype this problem line and [r] |jj] [^] it again, Sam
(excuse us, VIC!!). Birds! Birds! Everywhere!! In every color
of the rainbow! Your screen should be humming (oops!) with
flocks of "rainbow" birds. Notice thai there are gaps in your
flock. Actually, the VIC is PRINTing white birds in those
places. If you want these "invisible" birds to appear, you
mus1 change the background color. (Remember how? You
POKE a number into location 36879.)
Of course, if you change the background to another colon
say blue, then all the blue birds will disappear. Try it and see
tor yourself. Press EE1 when you want to keep the birds
from Hying. *■■*
The last example used some interesting VIC features to get
the birds on the screen and change their colors. Let's look
at the example line-by-line. The first line is:
1 A$ = " I
The color controls form a long string of characters
are put into the VIC'S memory in a place called AS
(pronounced "A string" or "A dollar sign"). You can think of
AS as being like a box where strings of characters can be
stored. The first position in the box A$ contains
control character. The last position contains the
control character.
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